重铬酸钾快速测定化学耗氧量方法研究与检验

Study and inspection on an express determination method chemical oxygen demand by potassium dichromate

本方法适当提高硫酸浓度 ,强化了重铬酸钾的氧化效率 ,使回流时间由 2h缩短到 10min ;并且用硝酸银和硝酸铋联合掩蔽法能消除氯离子的干扰 ,代替剧毒的硫酸汞。通过对标准样品的测定及测定结果的统计检验 ,证明此法与标准方法测定结果无显著性差异且有相同的精密度 。

This method raises sulfuric acid concentration properly and strengthens oxidation efficiency of potassium dichromate. The round trip flow time is cut short from two hours to ten minutes and the method adopts silver nitrate-bismuth nitrate united screening method to eliminate the disturb of chorine ion instead of strenuous noxious mercury sulfuric. Through the determination of the standard sample and the statistical inspection of the determination results, this method is verified that it is notable indifferent from the standard one. But the two methods have the same precisions and exits quite marked linear relation.